How to Check if an Electric Baseboard Heater Is Broken

Without air circulation, electric baseboard heaters overheat.

Electric baseboard heaters, like most electric heaters, have conducting elements that heat up when electricity passes through them, and it seems there isn't much that can go wrong. Despite that, baseboard heating systems malfunction regularly, and although the cause is usually something easily to fix, it can be difficult to find. There are three places to look: the circuit breaker panel, the thermostat and inside the heater itself. It's best to start with the panel because problems there are easy to spot. The next place to look is the thermostat, and if that checks out, the heater itself is probably faulty.

1

Turn off the thermostat control. It may be on the heater itself or on the wall. Open the main panel door and look for a tripped breaker. If the heaters are on a 240-volt circuit, you may find a couple pair of breakers tripped. Reset the tripped breaker. If it trips again, there's a problem with the electrical circuit -- not the heater.

2

Watch the breaker -- if it stays on -- while someone turns on the heater thermostat. If the breaker trips as soon as the thermostat goes on, there's probably a short in the wire that goes to the thermostat, in the thermostat itself or in the connection between the thermostat and the heater.

3

Keep your eye on the breaker if it doesn't trip as soon as you turn on the thermostat. It may trip when the heater comes on -- a minute or two after turning on the thermostat. If so, that's a problem with the heater.

4

Inspect the thermostat for shorts, using a multimeter set to measure resistance in ohms. Conduct this test if the breaker trips when you turn the thermostat on or if the breaker stays on but the heater doesn't come on. To perform the test, turn off the circuit breaker and then take the thermostat off the wall, using a screwdriver.

5

Remove all the thermostat wires from the control. Touch one lead to each wire while you hold the other lead on the ground wire. Repeat the test with all the thermostat terminals. Any wire or terminal that produces a "0" reading for resistance is shorted and must be repaired.

Things You Will Need

Multimeter

Screwdriver

Tip

If the thermostat is working and the circuit breaker hasn't tripped, the heater needs servicing. Its internal temperature-limiting fuse may have blown, or the heater may be dirty. Vacuum out any dust and ensure the fan is clean.

If the heater is plugged into an outlet, unplug the heater and plug another appliance or light fixture into the outlet to ensure there's power. If the outlet is a GFCI, its internal breaker may have tripped. Outlets can also lose power when another GFCI on the circuit trips.

Warning

Do not touch any electrical wires in the heater or the thermostat without first turning off the circuit breaker. You can get a serious -- even fatal -- shock.